Chapter 183: Benzodiazepines

INTRODUCTION

Benzodiazepines, to varying degrees, have in common six major pharmacologic effects: sedative, hypnotic, anxiolytic, amnestic, anticonvulsant, and muscle relaxant.¹ Benzodiazepines are commonly used for the short-term treatment of anxiety, insomnia, seizures, and alcohol and sedative-hypnotic withdrawal.^2,3,4,5 The long-term benefits of benzodiazepines for psychiatric disorders are controversial.^6,7 Midazolam, a benzodiazepine with a short duration of action, is also used for procedural sedation and general anesthesia (Table 183–1).

Isolated benzodiazepine overdose has low mortality, and death is rare.⁸ However, increased rates of morbidity do result from mixed overdose, especially in combination with opioids. Isolated overdose with high-potency short-acting agents, such as alprazolam, temazepam, and triazolam, is associated with higher incidences of intensive care unit admissions, coma, and mechanical ventilation with toxicity compared to other benzodiazepines, such as diazepam.⁹ In the ED, parenteral administration of benzodiazepines may result in significant complications, particularly respiratory depression and hypotension, especially when combined with opioids or other sedatives.

PHARMACOLOGY

Benzodiazepines stimulate the α subunit of the postsynaptic γ-aminobutyric acid ...